This application proposes continued analysis of longitudinal data from the NIMH Epidemiologic Catchment (ECA) Area Program. The ECA Program of two-wave field surveys at five U.S. sites yielded more than 15,000 person years of experience, with a broad range of symptom and diagnostic data on psychopathology. The foci of the work continue to be the search for syndromes and the study of the onset of psychopathology in the population, for which these data are uniquely suited. Work during the prior award period has resulted in more than 20 scientific papers in four areas: 1) conceptual and methodologic issues: 2) presentation of benchmark incidence data, 3) risk factor analyses of incidence for major mental disorders 4) quantitative taxonomic analyses on important nosologic issues such as the distinction between anxiety and depression. Future work will focus on 1) The search for, and verification of, syndromes and disorders including DIS/DSM-III disorders. Methods in this area include polytomous logistic regression and extensions of probit regression. 2) Prospective analysis of one important risk factor as yet not analyzed-- family and household status. Here the analytic technique is likely to be conditional logistic regression. 3) Examination of two potent biases in psychiatric research-- Berkson's bias and Neyman bias. Polytomous logistic regression is appropriate for these analyses. 4) Comparison of our data on incidence with data from three other field studies of incidence. A four day workshop is proposed for this purpose. Results of these analyses will provide empirical support for some DSM-III syndromes and disorders, and suggest new ones that should be explored. Results of analyses on family and household composition will provide an empirical basis for prospective research, and an estimate of the importance of these factors for incidence of mental disorders. Results of analyses of Berkson's and Neyman bias will help evaluate the generalizability of much psychiatric research conducted in clinical settings. The incidence workshop will integrate ECA data into world research, test the robustness of the incidence and risk factor results, and provide a vehicle for evaluation by clinicians of the implications of ECA results as regards psychiatric nosology